1. Field of the Invention
This invention relates to a hitch for towing a pair of wheel supported implements behind a towing vehicle selectively in one of: a transport position and either of two working positions by manual or power operation of a control device without the necessity of disconnecting, repositioning and reconnecting the implements.
More particularly the invention related to an adjustable hitch for towing a pair of side delivery rakes, or the like, selectively in one of: a transport position with one rake trailing the other in tandem, a single windrowing position with one rake trailing and offset to one side from the other to combine the hay picked up by each rake into a single windrow, and a double windrow position with one rake trailing and offset to the other side of the other rake wherein each rake delivers a separate windrow.
2. Discussion of the Prior Art
With the introduction of more powerful tractors in recent years, it has become economically importent, both from the standpoint of saving time and energy to connect implements in multiple to a towing vehicle. Various hitches have been developed for this purpose which are most commonly designed for use with particular implements each of which requires that certain features be designed into the hitch to meet the requirements of the implements when being transported or when in use. For transport it is commonly required that the implements be towed in tamdem directly behind each other so as to occupy only one traffic lane of a highway, whereas for field use the implements must be offset to the right or left of each other.
The present hitch has been designed specifically for use in towing a pair of similar side delivery rakes of a type disclosed, for example, in U.S. Pat. No. 2,781,626 issued Feb. 19, 1957. The rakes each include a rotating side delivery rake reel mounted on a wheeled frame which is adapted to be towed behind a towing vehicle. If the rakes are built for left hand side delivery, one rake can be staggered to the left and rear of another rake in order that the one rake will pick up the hay delivered by the forward rake and in addition will rake up hay in the area over which it travels. This combines the output of the two rakes to produce a single large windrow. The two left hand delivery rakes can be towed with one trailing behind and offset to the right of the other so that each rake produces its own separate windrow. If the rakes are built for right hand side delivery, the trailing rake must be offset to the right in order to produce a single combined windrow, and offset to the left in order that each rake will deliver its own separate windrow.
One prior art hitch for connecting a pair of side delivery rakes to a towing vehicle generally for the purpose just described is disclosed in U.S. Pat. No. 3,077,722, issued Feb. 19, 1963 to Sadler et al. It comprises an L-shaped frame having a front transverse frame member and a longitudinal frame member extending rearwardly from one end of the transverse frame member. The frame is supported on the ground by a front caster wheel mounted on the free end of the transverse frame member, and a rear wheel rigidly secured adjacent the rear end of the longitudinal frame member. The frame is connected to the drawbar of a tractor by a bracket secured to the transverse frame member and a hitch member. Draw bars are attached to the rear of the transverse frame member adjacent to the front caster wheel for towing a first side delivery rake, and to the rear end of the longitudinal frame member for towing a second side delivery rake laterally offset from the first side delivery rake. In order to change the positions of the two rakes, connected to the hitch disclosed in U.S. Pat. No. 3,077,722, the tractor must be stopped and both rakes must be unhitched, the implement hitch must be physically turned over, and the rakes then reconnected to the hitch in different positions. Considerable time and physical labor on the part of an operator are required in repositioning the hitch and rakes.
In contrast to the hitch disclosed in U.S. Pat. No. 3,077,722, the present hitch is adjusted merely upon movement of a single control means without disconnecting the rakes from the hitch.
Other dual implement hitches of which applicant is aware are disclosed in the following U.S. Pat. Nos.:
______________________________________ 3,177,828 Cramer Apr. 13, 1965 3,292,948 McMasters et al Dec. 20, 1966 3,568,423 Hale et al Mar. 9, 1971 3,990,718 Holland Nov. 9, 1976 4,178,010 Gerber Dec. 11, 1979 4,245,458 Smith Jan. 20, 1981 ______________________________________
U.S. Pat. Nos. 3,568,423 and 4,245,458 disclose dual hitch frames for hay rakes which are structurally and functionaly substantially different from the present invention.
U.S. Pat. Nos. 3,177,828, 3,292,948 and 4,178,010 disclose dual hitch frames for various agricultural implements which differ structurally from the present invention particularly in the means for adjusting the hitch to reposition the towed implements without disconnecting the implements from the hitch.